`P_(c )=(a)/(27b^(2))=(0.751" L"^(2)" atm " mol^(-2))/(27xx(0.0226" L "mol^(-1))^(2))=54.5" atm"`
`T_(c )=(8a)/(27"Rb")=(8xx0.75" L"^(2)" atm " mol^(-2))/(27xx0.0821" L atm "K^(-1)mol^(-1)xx0.0226" L " mol^(-1))=120 K`
`V_(c )=3 b=3xx0.0226" L " mol^(-1)=0.0678" L "mol^(-1)`.